unicellular Single-celled.
uniformitarianism The idea that geological processes have remained uniform over time and that slight changes over long periods can have large-scale consequences; proposed by James Hutton in 1795 and re?
unicellular
made up of one cell.
upper epidermis
the tissue in plants, usually one cell thick, that is on the top surface of the leaf.
Unicellular or multicellular photosynthetic eukaryotes that generally lack roots, stems, leaves, conducting vessels, and complex sex organs. Formerly, photosynthetic bacteria were also called algae, but this usage is now obsolete.
unicellular microbes like E. coli
unicellular eukaryotes like yeast and
in mammalian cells grown in tissue culture.
unicellular (cytoplasmic) organization The life-form in which all functions are carried out within the confines of a single plasma membrane; members of the kingdom Protista display unicellular organization; also called cytoplasmic organization.
Unicellular organisms may also respond to environmental stimuli via the activation of signal transduction pathways. For example slime molds secrete cyclic AMP upon starvation which stimulates individual cells in the immediate environment to aggregate.
A unicellular fungus that lives in liquid or moist habitats, primarily reproducing asexually by simple cell division or by budding of a parent cell.
yolk
The stored food in egg cells that nourishes the embryo.
Spore
Unicellular often environmentally resistant dormant or reproductive body produced by plants and some microorganisms and capable of development into a new individual either directly or after fusion with another spore.
Genus of unicellular organisms, some of which are pathogenic to man and animals. They are found living in close association with man, animals and their environments.
spherical unicellular organism
Source: Noland, George B. 1983. General Biology, 11th Edition. St. Louis, MO. C. V. Mosby
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For simple unicellular organisms such as the Amoeba, one cell division reproduces an entire organism. On a larger scale, cell division can create progeny from multicellular organisms, such as plants that grow from cuttings.
A unicellular form of fungi. Some fungi (for example Saccharomyces cerevisiae) are only known to reproduce as yeast while other fungi (for example, Candida albicans) are dimorphic, ...
microscopic unicellular algae. most are aquatic, being found in fresh, brackish, and salt water. Diatoms are noted for the symmetry and sculpturing of their siliceous cell walls.
Fungi contain unicellular, multinucleate, and multicellular forms.They are classified on the basis of their reproductive spores and the nature of their multinucleate or multicellular filaments known as hyphae.
In addition, only unicellular organisms (or organisms with totipotent cell lines) can have an evolutionary benefit from this mode of mutation.
Cyanobacteria: Unicellular, photosynthetic (photo-autotroph) prokaryote (in the Kingdom Monera). Formerly known as blue-green algae. It contains chlorophyll a but not chloroplast. They reproduce by fission and never sexually.
Flagellum - an extension on many unicellular organisms that enables movement through whip-like motions ...
The kingdom Protista as it now stands includes the unicellular and a few simple multicellular eukaryotic organisms with no well defined tissues or organs.
Prochlorococcus and Synechococcus are unicellular picoplankton, which are major biomass producers in the world's temperate and tropical oceans.
As illustrated in Figure 1, for example, many unicellular organisms and certain cells in multicellular organisms consume particles of food and other items via a process called phagocytosis.
(See the Proteins and Proteomics unit.) In 2003 Roderick MacKinnon and his colleagues used this technique to examine the structure of a voltage-gated potassium channel from a unicellular archaea.
The Moneran Kingdom consists of unicellular life forms. Unicellular means that they only have one cell. Moneran cells are far simpler and more basic than the cells of other life forms.
Diatoms are very common unicellular algae that have a characteristic cell wall of silica. They exhibit a wide variety of shapes, some quite exquisite.
All living organisms, whether unicellular or multicellular exhibit homeostasis.
Once the process was refined, unicellular organisms became able to eat other objects that were almost as big as they were. They were also able to become independent of processes like diffusion and active transport.
colonial -- Condition in which many unicellular organisms live together in a somewhat coordinated group. Unlike true multicellular organisms, the individual cells retain their separate identities, and usually, their own membranes and cell walls.
Acetabularia - genus of unicellular marine algae. These organisms comprise an enormous single cell consisting of a cap, stalk and rhizoid and can be up to 10 cm in size.
Cilia are hair-like structures that can beat in synchrony causing the movement of unicellular paramecium. Cilia are also found in specialize linings in eukaryotes.
Some of the unicellular protozoa contain no nuclei but granular particles which, like true nuclei, stain with basic dyes. The other constituents of the ovum, viz.
The Subkingdom of the Kingdom Animalia, in older classification systems, that includes all unicellular organisms that lack differentiated tissues and that primarily reproduce through asexual means, although conjugation does occur.
is the ability of an open system to regulate its internal environment to maintain stable conditions by means of multiple dynamic equilibrium adjustments controlled by interrelated regulation mechanisms. All living organisms, whether unicellular or ...
only one cell, for example bacteria, protists and some fungi (for example yeasts and molds); however, although in quantity and/or volume a multicellular organism possesses more matter, they will not be more complex or more ordered than a unicellular ...
 See also: Organ, Cells, Plant, Cell, Trans
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